iBasso D2-Viper (Pictures, Impressions, and Reviews): Read the Rules! - Page 41

thanks for notice me

where can i get op amps????? i have ultrasone 750's, which op amps are best for my d2 viper? can someone give me general information. what is needed etc,,,

i know nothing about op amps and rolling and whatever, i just want basic info and what I can do.. thanks!

Some info here:
http://www.head-fi.org/forums/f5/opa...per-d2-308023/

I finally got around to swapping the LM6172 in the main socket and THS4032 in the ground channel.

The original combo was best with things like my Grado RS-1, but too forward in the mids and rolled off in the treble for my Freq Show IEM or a-JAYS. With the opamps swapped it is perfect for the Freq Shows, q-JAYS, Denon D2000, HD600, but too shrill or treble boosted for the RS-1 (APS V3 cabled).

Swapping the THS4032 for the AD8397 was similar, as was the ISL55002, but the LT134 is still a little rolled off, while the AD8397 is maybe slightly brighter but a little edgier.

Can anyone give advice of improving the "scratchy" sound from the volume pot? i don't really mind the scratchy sound when actually adjusting the volume but mine is now making a sort of scratchy static sound in the background constantly even when not adjusting the volume. If i make minute changes i can limit the static but can not completely get rid of it.

I might try changing back to the original opamps and see if that fixes things... i haven't changed opamps in a while but remember they would change the loudness of the gain switch popping sound... so might also improve the sensitivity of the volume static?

Edit: i remember ages ago someone mentioned they replaced the volume pot but can't find the post

Edit: found kinda what i was after:
http://www.head-fi.org/forums/f5/opa...23/index2.html

Basing on HiFlight's suggestion, I rolled my D2 Viper using LTC6241HV and the LMH6655. Initial hearing, the sound is much better than the original opamps. Just rolled a few minutes back. Will have to let the burning starts.

Good recommendations, Ron

Be careful when plugging in and unplugging headphones with the power on and volume at normal volumes, as this caused my LTC6241HV to blow/fry/die. There is always a brief short in one of the channels as a headphone plug goes in or out, and the chip/amp combo does not like it. I also blew/killed an LTC6241HV in my Travagans Reg, but I am not sure whether it was when I first turned on the amp or from plugging in headphones.

Also, make sure that you put the opamps in the socket in the correct polarity. I fried my TSH4032 this way There was a bit of smoke and everything

It's always a drag when you let the factory smoke out of electronics. The aftermarket replacement smoke is never quite as good, and it is a real b!tch getting the smoke back into the chips...

Hmmm ... no smoke but nice, sweet music coming out from my headphone Next step is looking for a better headphone over my present Sennheiser R130 wireless.

quick question about the viper pls help.  I just mine today, does it work like the Boa where the aux in works as a line level out when the usb is plugged in? or do I run the 1/4" to RCA through the headphone out to connect to my amp? thanks

My recollection is there is no line out, so you use the headphone out to feed another amp.

thanks, I know that that is not really the ideal way to send signal to an amp, but since that is how I am doing it for now, what volume level would be good on the D2? 

I would turn down the volume of the amp you are going to listen to, and then plug the D2 into it as a source.  Then turn on the D2 first at zero volume, followed by turning on the second amp which I would set to about 3 o'clock (turn this on second in case you get a pop from turning on the D2 which you don't want to amplify).  And then with music playing I'd work the D2 volume control up to a normal listening level, while not touching the target amp volume if you don't need to.  This is basically using the D2 as a pre-amp.  If you turn the second amp to full volume you might get too much noise, which is why I suggested 3 o'clock.

thanks I will try that..